CN102644009A

CN102644009A - Aluminum-alloy multi-layered sheet

Info

Publication number: CN102644009A
Application number: CN2012100933601A
Authority: CN
Inventors: 松本克史; 田村荣一; 杵渊雅男; 植田利树; 腰越史浩; 木村申平
Original assignee: Kobe Steel Ltd
Current assignee: Kobe Steel Ltd
Priority date: 2008-02-12
Filing date: 2009-02-05
Publication date: 2012-08-22
Anticipated expiration: 2029-02-05
Also published as: EP2479303A1; CN101918601A; CN102644009B; EP2248924A1; WO2009101896A1; CN104708867A; US20110014494A1; EP2248924A4; EP2248924A8; US8343635B2

Abstract

Provided is a multi-layered sheet which has undergone heating corresponding to brazing, such as an aluminum-alloy radiator tube, or a multi-layered sheet such as an aluminum-alloy brazing sheet. The multi-layered sheet can have a reduced thickness and has excellent fatigue properties. The multi-layered sheet of aluminum alloys comprises a core layer (2) which has been clad at least with a sacrificial layer (3). This multi-layered sheet is a multi-layered sheet to be subjected to brazing or welding to produce a heat exchanger or is a multi-layered sheet which has undergone heating corresponding to brazing. The core layer (2) comprises a specific 3000-series composition. In this core layer (2), the average density in number of dispersed particles having a specific size has been regulated. As a result, fatigue properties, which govern cracking, can be highly improved.

Description

Aluminum alloy laminate

The application is to be 200980102028.3 (PCT/JP2009/051998), denomination of invention dividing an application for " aluminum alloy laminate " in the application number that on February 5th, 2009 submitted.

Technical field

The present invention relates to the aluminum alloy laminate that Al-alloy heat exchanger uses (following also aluminium is called Al), especially relate to the aluminum alloy laminate of excellent in fatigue characteristics.Among the present invention; Provide a kind of and comprise the core aluminium alloy plate at least and be coated on aluminium alloy plate on the said core aluminium alloy plate and sacrifice the laminated wood of impregnating material, the heat exchanger that will be used in heat exchanger through soldering also is called aluminum alloy laminate, carries out the aluminum alloy laminate before the heating suitable with soldering or only is called the layer of feed stock material plywood with starting material.In addition; With comprising that at least core aluminium alloy plate and the aluminium alloy plate that is coated on the said core aluminium alloy plate sacrifice impregnating material, the laminated wood of having implemented to be equivalent to the heat treated of soldering also is called and has carried out the aluminum alloy laminate after the heating suitable with soldering or only be called the laminated wood that has carried out after the heating suitable with soldering.

Background technology

For the body lightening of automobile, in the heat-exchanging part of automobile, replace present employed Cu alloy material and use the situation of aluminum alloy materials also to increase.And these heat-exchanging parts use the corrosion stability aluminum alloy materials that constitutes by by the laminated wood of multiple stratification (also being called cladding plate, coating material) with aluminum alloy materials.

This laminated wood is being assembled under the situation of heat exchanger through soldering, and the one side that constitutes at duraluminum coremaking material has coated the structure that duraluminum is sacrificed impregnating material (plate), coated the brazing sheet of aluminium alloy brazing material (plate) at another side.

Fig. 4 representes the example of duraluminum system automobile with heat exchanger (scatterer).As shown in Figure 4, scatterer 100 is formed with and is processed into undulatory duraluminum system radiator element 112 normally between the flat piped duraluminum system radiator tube 111 of many settings.These pipe two ends of 111 be respectively to the structure by the space opening of collector (header) 113 and water storage tank (not shown) formation.The scatterer 100 of this structure will be from the space of on one side water storage tank through managing the refrigeration agents that reach a high temperature in 111; Be transported to the space of another water storage tank one side; Carry out heat exchange at the pipe 111 and the part of radiator element 112, make to become refrigerant of low temperature and carry out recycling.

This aluminium alloy material tubulation 111 is made up of duraluminum system brazing sheet 101.Fig. 5 representes the section of duraluminum system brazing sheet 101.In this Fig. 5, range upon range of (coating) has duraluminum system sacrificial anode material (also being called the skin material) 103 to brazing sheet 101 in a side of duraluminum coremaking material 102, and range upon range of (coating) has duraluminum system solder 104 in the another side of core 102.Also have, under situation, constitute the laminated wood that only is covered with duraluminum sacrifice impregnating material 103 at the bread of a side for duraluminum system cladded sheet materials.

This duraluminum system brazing sheet 101 forms flat tubulose through forming roll etc., and through resistance welding or soldering heating, brazing sheet 101 self is formed the fluid passage as the pipe 111 of Fig. 4 by soldering.

The principal constituent of the refrigeration agent of scatterer (refrigerant) is water-soluble medium, uses the refrigeration agent wherein suitably contain commercially available rust-preventive agent etc.But under the situation of using such refrigeration agent, exist because rust-preventive agent etc. lasted the acid that is generated after the deterioration, the problem that causes aluminum alloy materials such as said expendable material or core to be corroded easily and so on.Therefore, must use the aluminum alloy materials that water-soluble medium are had high corrosion stability.

Therefore; Consider from the viewpoint of corrosion stability and intensity; Brazing sheet and be used for the duraluminum coremaking material 102 of the laminated wood of covering piece uses (3000 are) alloy such as system such as 3003 Al-Mn such as grade that for example is made up of compositions such as Al-0.15 quality %Cu-1.1 quality %Mn of defined among the JISH4000.In addition, the high strength that forms to the diffusion of core 102 with against corrosion and Mg is a purpose, in the skin material 103 that contact with refrigeration agent often, uses and 7072 Al-Zn such as grade that constitute such as forms by Al-1 quality %Zn and be or Al-Zn-Mg is (7000 are) alloy.In addition, solder 104 uses (4000 are) alloy such as system such as 4045 Al-Si such as grade that constitutes of forming by low-melting Al-10 quality %Si etc.

Scatterer 100 adopts the pipe 111 that uses this brazing sheet 101 to form, radiator element 112 and other parts that carried out ripple processing, is assembled into one through brazing.As the gimmick of brazing, soldering flux brazing (flux brazing) method is arranged, use aluminum brazing flux (Nocolok) braze welding of noncorrosive soldering flux etc., the high temperature that is heated to about 600 ℃ carries out soldering.

In the scatterer that so is assembled into 100, particularly manage in 111, from high temperature to low temperature and from high pressure, carry out circulation cycle often to non-pressurized aforesaid liquid refrigerant.That is,, therefore require pipe 111 to have the fatigue characteristic of these stress of tolerance owing to press the long-time additional repeated stresses such as vibration of change or automobile self in these.Suppose under low in fatigue characteristic, as the to produce fatigure failure situation, fatigure failure as the crackle of pipe 111 take place, progress, if through tube 111 then becomes the reason from the scatterer seepage.Therefore, the improvement of the fatigue characteristic of radiator tube is important problem.

At present, the improvement of the fatigue characteristic of this radiator tube puts forward various plans.For example; In the patent documentation 1, the core of duraluminum system brazing sheet is to contain Cu, Ti, Mn, and limits the duraluminum of Si, Fe, Mg; Average crystal grain diameter L through the rolling direction in the longitudinal section that makes core is 150～200 μ m; Improve the corrosion stability of the weld part of pipe, thus the fatigure failure property that the alternating bending of improvement pipe causes, i.e. anti-the shake fatigue characteristic of automobile under vibration.In the patent documentation 2; The average crystal grain diameter of the thickness direction through will sacrificing the impregnating material side is set at and is lower than the thickness of sacrificing impregnating material; Improve the corrosion stability of sacrificing impregnating material, thereby the fatigure failure property that the alternating bending of improvement pipe and interior pressure load repeatedly cause is fatigue characteristic.

In addition, known fatigue characteristic are relevant with static tensile strength usually, in heat exchanger, for example as patent documentation 3, proposed to have added in order to improve raw-material tensile strength the material of Cu.And, in the patent documentation 4, improve the anti-fatigue characteristic of shaking through systematical improvement.Promptly; In the patent documentation 4; Following scheme has been proposed; That is, in the heat exchanger of the aluminum alloy brazing sheet of the three-layer structure of the duraluminum expendable material that be coated with the duraluminum core, the aluminium alloy brazing filler metal that contain Cu in use, contains Zn and Mg, making specific Al-Cu-Mg-Zn is the core side interface portion of the near interface of the precipitate core and the expendable material that are distributed in the brazing sheet after the soldering.This is to be the age hardening that precipitate carries out through Al-Cu-Mg-Zn, improves the intensity of core side interface portion, and thus, improving the fatigure failure property that interior pressure load repeatedly causes is the method for fatigue characteristic.

In addition; In the patent documentation 5; With the set tissue of X-ray diffraction intensity than regulation duraluminum system brazing sheet, this duraluminum system brazing sheet is that the core of alloy, the lateral Al-Zn that is coated on this core are that the skin material of alloy etc., the Al-Si that is coated on the another side of this core are that the solder of alloy constitutes by Al-Mn.In the patent documentation 5, the brazing sheet takes place on the viscous deformation easy and uniform ground of the direction that parallels with rolling direction.Thus, even stretch or the repeated stress of compression at the rolling direction of brazing sheet load, because distortion can not concentrate partly, therefore be full of cracks can improve the life-span of the brazing sheet of the fatigue that comprises plastic region to the making slow progress of thickness of slab direction.

In addition; Be not by the brazing sheet in order to improve; But the corrosion stability of the radiator element that is made up of 3000 identical line aluminium alloys has proposed crystallisate and the shape of intermetallic compound and the technology (for example with reference to patent documentation 6,7,8) that number density is stipulated in the tissue.If, will cause the disappearance of sheet self, so corrosion stability is very important because this radiator element is corroded.Therefore, the crystallisate in the tissue of being put down in writing in the patent documentation 6,7,8, the shape of intermetallic compound and the regulation of number density also are closely connected with the distinctive technical problem of radiator element that improves corrosion stability and so on.

Patent documentation 1: Japanese publication communique: 2003-82427

Patent documentation 2: Japanese publication communique: 11-100628

Patent documentation 3: Japanese publication communique: 10-53827

Patent documentation 4: Japanese publication communique: 9-95749

Patent documentation 5: Japanese publication communique: 2006-291311

Patent documentation 6: Japanese publication communique: 9-78168

Patent documentation 7: Japanese publication communique: 2000-119783

Patent documentation 8: Japanese publication communique: 2005-139505

But the scatterer tube wall of these existing automobiles is thicker.For example; In aforementioned each patent documentation; With the thickness of slab (total thickness of slab) of the brazing sheet of the object estimated as resistent fatigue characteristic be with reference to the time, be to be to be 0.20mm in 0.25mm, the patent documentation 4 and 5 in 0.4mm, the patent documentation 2 in the patent documentation 1, whole thickness of slab is more than the 0.20mm.But the automobile lightweight owing to improving for the combustion expense that is related to the global environment problem is also requiring the lightweight of scatterer.Therefore, studying scatterer pipe, be the thin-walled property further of duraluminum system brazing sheet.

At radiator tube is under the thicker situation of the such wall ratio of 0.4mm degree, and the pipe self rigidity is than higher.Relative therewith, mainly be under the situation of thickness of slab thin-walled property of laminated wood such as brazing sheet at radiator tube, pipe self rigidity step-down.What on the other hand, the pressure of employed refrigeration agent was set mostly is higher than in the past.Under the situation of the thickness of slab thin-walled property of laminated woods such as brazing sheet, since their synergy, the tendency that the susceptibility with fatigure failure that aforementioned repeated stress is caused increases, fatigue characteristic reduce.

Radiator tube generation of cracks (crackle, crack) has taken place under the situation of this fatigure failure.Under by the situation of the radiator tube of thin-walled property, this be full of cracks through tube causes that the possibility that the liquid of scatterer leaks is high, therefore, becomes more serious damage.

But, by the fatigue characteristic of the radiator tube behind the thin-walled property, also do not find effectively to improve strategy up to now about like this.Effectively improving tactfully when undiscovered at this, radiator tube, is that laminated wood such as duraluminum system brazing sheet can not thin-walled property, to the lightweight of scatterer and then the very big restriction of lightweight meeting generation of automobile.

Summary of the invention

In view of such problem, but the object of the present invention is to provide the aluminum alloy laminate of thin-walled property such as aluminum alloy brazing sheet that a kind of radiator tube of heat exchanger uses and excellent in fatigue characteristics.

In order to realize this purpose; The aluminum alloy laminate of the application's first invention; It comprises the core aluminium alloy plate at least and is coated on the anticorrosion duraluminum expendable material of using on the said core aluminium alloy plate; And be used in heat exchanger through soldering; It is characterized in that said core aluminium alloy plate is that following duraluminum is formed: contain Si:0.2～1.5 quality %, Cu:0.2～1.2 quality %, Mn:0.2～1.4 quality %, Ti:0.03～0.3 quality % respectively, and contain below the Fe:1.0 quality %; Surplus is made up of Al and unavoidable impurities, and has like undertissue: the MV at rolling surface skin section observed center of gravity diameter through 500 times SEM of this core aluminium alloy plate is that the average number density of the dispersed particle more than the 1 μ m is 7000/mm ²Below.

In addition; To achieve these goals; The aluminum alloy laminate of the application's second invention; It comprises at least the core aluminium alloy plate be coated on anticorrosion on the said core aluminium alloy plate with the duraluminum expendable material, and, it is characterized in that said core aluminium alloy plate is following duraluminum composition: in quality % through soldering formation heat exchanger; Contain Si:0.2～1.5 quality %, Cu:0.05～1.2 quality %, Mn:0.3～1.8 quality %, Ti:0.03～0.3 quality % respectively; And contain below the Fe:1.0 quality %, surplus is made up of Al and unavoidable impurities, and has like undertissue: this core aluminium alloy plate be that the average number density of the precipitate of 0.1～0.5 mu m range is 150/μ m at the MV of rolling surface thickness of slab central part through the observed center of gravity diameter of 50000 times TEM ³Below.

To achieve these goals; The aluminum alloy laminate of the application's the 3rd invention; It includes the core aluminium alloy plate at least and is coated on the anticorrosion duraluminum expendable material of using on the said core aluminium alloy plate; It is characterized in that; Said core aluminium alloy plate is that following duraluminum is formed: it contains Si:0.2～1.5 quality %, Cu:0.2～1.2 quality %, Mn:0.2～1.4 quality %, Ti:0.03～0.3 quality % respectively, and contains below the Fe:1.0 quality %, and surplus is made up of Al and unavoidable impurities; As the tissue after the heating that is equivalent to soldering; It has following tissue: the average crystal grain diameter of the rolling direction in the longitudinal section of rolling direction of this core aluminium alloy plate is below the 200 μ m, and the MV at rolling surface skin section observed center of gravity diameter through 500 times SEM of this core aluminium alloy plate is that the average number density of the dispersed particle more than the 1 μ m is 6000/mm ²Below.

In addition; To achieve these goals; The aluminum alloy laminate of the application's the 4th invention, it comprises the core aluminium alloy plate at least and is coated on the anticorrosion duraluminum expendable material of using on the said core aluminium alloy plate, it is characterized in that; Said core aluminium alloy plate is that following duraluminum is formed; Said duraluminum composition contains Si:0.2～1.5 quality %, Cu:0.05～1.2 quality %, Mn:0.3～1.8 quality %, Ti:0.03～0.3 quality % respectively, and contains below the Fe:1.0 quality %, and surplus is made up of Al and unavoidable impurities; As the tissue after the heating that is equivalent to soldering; It has following tissue: the average crystal grain diameter of the rolling direction in the longitudinal section of rolling direction of this core aluminium alloy plate is below the 200 μ m, and, this core aluminium alloy plate be that the average number density of the precipitate of 0.1～0.5 mu m range is 80/μ m at the MV of rolling surface thickness of slab central part through the observed center of gravity diameter of 50000 times TEM ³Below.

At this, said the application's first invention to the core aluminium alloy plate in the laminated wood of the 4th invention preferably also has following structure:

Contain among Cr:0.03～0.3 quality %, Zn:0.2～1.0 quality %, the Zr:0.03～0.3 quality % one or more.

Contain below the Mg:0.5 quality %.

Thickness of slab is the thin-walled that is lower than 0.25mm.

In addition, the thickness of slab of said the application's first invention to the laminated wood of the 4th invention is preferably the thin-walled that is lower than 0.3mm.

The invention effect

Present inventor etc. to the thickness of slab of said laminated wood by thin-walled property after the principle of fatigure failure in fatigue characteristic seek.Consequently, can know according to present inventor's opinion, the thickness of slab of laminated wood by thin-walled property after fatigure failure principle in fatigue characteristic have two kinds.That is, in the principle of fatigure failure, the propagation (speed) of the be full of cracks (crackle, crack) that causes than fatigure failure is arranged, the reigning situation of the generation of be full of cracks; And the generation of the be full of cracks (crackle, crack) that causes than fatigure failure, the reigning situation of crevasse crack propagation (speed).And discoveries such as present inventor are used to improve effective means on the metallurgy of fatigue characteristic with respect to the principle of these two kinds of fatigure failures and have nothing in common with each other.

The propagation (speed) of the be full of cracks (crackle, crack) that causes than fatigure failure; When dominating role has taken place in be full of cracks; The easness that this be full of cracks takes place is constituted the tissue, promptly of core aluminium alloy plate of the said laminated wood of heat exchanger to a great extent, the influence of the average number density of average crystal grain diameter and thicker dispersed particle.

With respect to this; The generation of the be full of cracks (crackle, crack) that causes than fatigure failure; When crevasse crack propagation (speed) plays dominating role; The propagation of this fatigure failure (speed) is constituted the tissue, promptly of core aluminium alloy plate of the laminated wood of heat exchanger to a great extent, the influence of the average number density of average crystal grain diameter and finer precipitate.

The application first invention and the 3rd invention make the propagation (speed) of the be full of cracks (crackle, crack) that causes than fatigure failure, the fatigue characteristic raising when dominating role has taken place in be full of cracks.Thereby; As stated; For as constitute heat exchanger before the heat exchanger with the tissue of the core aluminium alloy plate in the raw-material laminated wood that carries out before the heating suitable with soldering, perhaps, carried out the tissue of the core aluminium alloy plate in the laminated wood after the heating suitable with soldering; Through the average number density of average crystal grain diameter and thicker dispersed particle is carried out organizational controls, the generation that suppresses to chap.

The application second invention and the 4th invention make the generation of the be full of cracks (crackle, crack) that causes than fatigure failure, and the fatigue characteristic the when propagation of fatigure failure (speed) plays dominating role improve.Thereby; As stated; For as constitute heat exchanger before the heat exchanger with the tissue of the core aluminium alloy plate in the raw-material laminated wood that carries out before the heating suitable with soldering, perhaps, carried out the tissue of the core aluminium alloy plate in the laminated wood after the heating suitable with soldering; Through the average number density of average crystal grain diameter and finer precipitate is controlled, suppress the propagation (speed) of fatigure failure.

In the application first invention and the 3rd invention, through making the average crystal grain diameter miniaturization of core aluminium alloy plate, and the average number density of the thicker dispersed particle of restriction ratio, thereby suppress the generation of fatigure failure itself.This result is, makes the propagation (speed) of the be full of cracks (crackle, crack) that causes than fatigure failure, raising fatigue lifetime (fatigue characteristic) of the laminated wood when dominating role has taken place in be full of cracks.

In the application second invention and the 4th invention, through making the average crystal grain diameter miniaturization of core aluminium alloy plate, and limit the average number density of fine precipitate, thereby suppress the propagation of fatigure failure.Consequently, the generation of the be full of cracks that causes than fatigure failure, improve the fatigue lifetime of the laminated wood the when propagation of fatigure failure plays dominating role (fatigue characteristic).

Said dispersed particle is meant that quilts such as alloying elements such as Si, Cu, Mn, Ti and Fe, Mg contain intermetallic compound or the intermetallic compound of these elements and Al between the element among the present invention; Itself and forming element (composition) are irrelevant, are can be according to the general name of the intermetallic compound of size identification through structure observation.

Description of drawings

[Fig. 1] is the sectional view of expression laminated wood of the present invention;

[Fig. 2] is the sectional view of expression aluminum alloy heat exchanger;

[Fig. 3] is the explanatory view of expression fatigue-bending test;

[Fig. 4] is the sectional view of the general aluminum alloy heat exchanger of expression;

[Fig. 5] is the sectional view of the general laminated woods such as brazing sheet of expression.

Nomenclature

1: heat exchanger is with aluminum alloy laminate, 2: core, 3: skin material, 4: solder, 10: scatterer (heat exchanger), 11: pipe (laminate component), 12: radiator element, 13: collector

Embodiment

Describe with Fig. 1,2 pairs of best modes that are used for embodiment of the present invention.Fig. 1 is the sectional view of heat exchanger of the present invention with aluminum alloy laminate, Fig. 2 be to use Fig. 1 laminated wood (aluminum alloy tube for heat exchanger) scatterer want portion's sectional view.Also have this Fig. 1,2 basic comprising, structure itself and above-mentioned Fig. 4,5 identical.

(laminated wood)

Laminated wood of the present invention at first is manufactured to aluminum alloy laminate shown in Figure 11 before being assembled into heat exchanger.This laminated wood 1 is configured as the brazing sheet, and it is coated with aluminium alloy plate and sacrifices impregnating material (plate) 3 when soldering in the side at core aluminium alloy plate 2, be coated with aluminium alloy brazing material (plate) 4 in the another side.

Above-mentioned core aluminium alloy plate 2 is made up of the tissue of the characteristic of stating after having and the JIS3000 line aluminium alloy of composition.In addition, a side (upside of Fig. 1) that promptly contacts often with refrigeration agent in the inboard of this core 2, as after the sacrifice impregnating material (expendable material, inner lining material, skin material) 3 stated and coat the duraluminum of the JIS7000 system etc. of Al-Zn composition for example.In addition, in the outside of core 2 (downside of Fig. 1), coat the aluminium alloy brazing filler metal 4 of the JIS4000 system etc. of Al-Si composition for example.

Laminated woods of the present invention such as brazing sheet be aforesaid be three layers of rolling coating material (plate) at center with core aluminium alloy plate 2.The thickness of slab of core aluminium alloy plate is lower than 0.25mm, and when for example being 0.16～0.24mm, the thickness of solder, sacrifice impregnating material all is 20～30 μ m degree usually.But its lining rate is different because of the thickness of slab (specification of purposes) of employed heat-exchanging part, and their value is unqualified.

But, the thickness of slab (mainly being the thickness of slab of core aluminium alloy plate) of laminated woods 1 such as brazing sheet, as stated, most important in the lightweight of heat exchanger.Thereby for the thickness of slab of laminated wood is lower than 0.3mm, preferred 0.16～0.29mm degree, the thickness of slab of core is lower than the thin plate of 0.25mm, preferred 0.16～0.24mm degree.

These brazing sheets are at the range upon range of sacrifice impregnating material of one side (plate) of having implemented the heat treated core aluminium alloy plate (ingot bar) that homogenizes and solder (plate) and carry out hot rolling, carry out cold rolling, process annealing, cold rolling then successively, make sheet materials such as H14 modulation material.At this, the thermal treatment that homogenizes also can be implemented before hot rolling.

(heat exchanger)

Utilize format roll etc. that aluminum alloy laminate 1 broad ways such as this brazing sheet is crooked, form flat tubulose with the mode that skin material 3 is disposed at the pipe inner face side after, form flat piped pipe through resistance welding etc.Expression is formed with the flat piped pipe (laminate component) 11 of fluid passage among Fig. 2.

As shown in Figure 2, this flat piped pipe (laminate component) 11 with the radiator element 12 that has carried out ripple processing with wait other members to become scatterer 10 heat exchangers such as grade (assembling) through brazing (brazing filler metal) integral production by collector 13.To manage (laminated member) 11 and radiator element 12 and be called the core body of heat exchanger by incorporate part.Through 585～620 ℃ more than the solidus temperature that is heated to solder 4, preferably be heated to 590～600 ℃ high temperature and carry out soldering.This Heating temperature surpasses 620 ℃ and when too high, can produce superfluous fusion or erosion etc.As this brazing constructional method, aluminum brazing flux (Nocolok) braze welding that soldering flux braze welding, the noncorrosive soldering flux of use are arranged that extensively adopts etc.

In the heat exchanger of Fig. 2, the space opening that the two ends of flat tube (laminate component) 11 are constituted to collector 13 and water storage tank (not shown) respectively.And, carry high temperature refrigerant from the space of on one side water storage tank side through the space to the water storage tank side of the other side in the flat tube 11, carry out heat exchange in the part of pipe 11 and radiator element 12, make to become refrigerant of low temperature and circulate once more.

(the core aluminium alloy plate tissue of the application's first invention and the 3rd invention)

At first the core aluminium alloy plate in the laminated wood of the application's first invention and the 3rd invention is described.

Core aluminium alloy plate in the laminated wood after carrying out the preceding laminated wood of the heating suitable with soldering (thermal process) or having carried out the heating suitable with soldering is made up of 3000 line aluminium alloys and is constituted.

In the application's first invention and the 3rd invention; Antifatigue during the generation of the be full of cracks that causes for the fatigure failure that improves this core aluminium alloy plate dominating role is destructive; Stipulate the average crystal grain diameter (only carried out the heating suitable after laminated wood) of the rolling direction in the longitudinal section of rolling direction of this core aluminium alloy plate, and stipulate the average number density (laminated wood after carrying out the laminated wood before the heating suitable and having carried out the heating suitable) of the dispersed particle that 1 μ m is above with soldering with soldering with soldering.

(crystal grain of the application's first invention and the 3rd invention)

Carried out in the preceding layer of feed stock material plywood of laminated wood or assembling (thermal process) after the heating suitable with soldering; Under the situation of thickization of average crystal grain diameter of core aluminium alloy plate, the destructive reduction of antifatigue of the reigning fatigue of generation of the be full of cracks that causes for fatigure failure.Thereby, make the average crystal grain diameter of the rolling direction in the longitudinal section of rolling direction of the core aluminium alloy plate in the laminated wood that has carried out after the heating suitable with soldering finely turn to below the 200 μ m, below the preferred 150 μ m.Also have; In order to make the core aluminium alloy plate miniaturization like this in the laminated wood that has carried out after the heating suitable with soldering, need certainly in advance average crystal grain diameter with the core aluminium alloy plate of layer of feed stock material plywood be set at below the 200 μ m, below the preferred 150 μ m.But; Even stipulated the average crystal grain diameter of the core aluminium alloy plate of layer of feed stock material plywood; For the laminated wood that has carried out after the heating suitable with soldering, because the heating condition of the soldering processing of heat exchanger when making etc. is different, average crystal grain diameter also can change (thickization).Therefore; Even stipulated the said average crystal grain diameter of core aluminium alloy plate in the layer of feed stock material plywood stage; Because said heating condition is different, also has and departs from afore mentioned rules and the possibility of thickization that become, and needn't specially stipulate in the stage of layer of feed stock material plywood.

Also have, said here crystal grain diameter is meant the crystal grain of the rolling direction in the longitudinal section (section of the plate after cutting off along rolling direction) of rolling direction.After this crystal grain diameter is with former material laminated wood and the longitudinal section of the rolling direction of the core aluminium alloy plate (extraction test portion) in the laminated wood after having carried out the heating suitable with soldering carries out pre-treatment through mechanical mill, electrolytically etching, observe with 50 times opticmicroscope.At this moment, draw a straight line, be used as each crystal grain diameter and the process of chopping (line intercept method) measured is measured the slice length that is positioned at each crystal grain on this straight line to said rolling direction.Carry out this mensuration at any 10 positions, calculate average crystal grain diameter.At this moment, measure line length for 1 and be made as more than the 0.5mm, the mensuration line in per 1 visual field is made as 3, observes 5 visuals field in per 1 location.Then, according to per 1 visual field (3 measure line), per 5 visuals field/per 1 location, per 10 location, to per 1 average crystal grain diameter of measuring the line sequentially determining averaging successively, as average crystal grain diameter of the present invention.

(dispersed particle of the application's first invention and the 3rd invention)

The core aluminium alloy plate is assembled into the laminated wood that carried out after the heating suitable with soldering when (packing into), must be heated to 600 ℃ and pay near temperature.Even stand this heat-processed, the above-mentioned chemical ingredients composition of stipulating among the present invention etc. can not change yet.But, because the solid solution of dispersed particle and thickization etc., to have carried out in the laminated wood after the heating suitable with soldering, the number density of the dispersed particle that the 1 μ m that stipulates among the present invention is above is towards changing than above-mentioned layer of feed stock material plywood direction still less.

In the application's first invention and the 3rd invention; For the pairing antifatigue destructiveness of the reigning fatigue of the generation that improves the be full of cracks that causes by fatigure failure; Above-mentioned layer of feed stock material plywood and carried out the heating suitable with soldering after the core aluminium alloy plate of laminated wood in; Average number density to the dispersed particle more than the 1 above-mentioned μ m limits, and it is not exceedingly increased.In other words, stood during soldering in the heat exchanger member of the heat-processed under near the temperature 600 ℃, the average number density of above-mentioned dispersed particle has been limited, it is not exceedingly increased.

The average number density of above-mentioned dispersed particle of having carried out the core aluminium alloy plate of the laminated wood after the heating suitable with soldering surpasses 6000/mm ²Situation under, the antifatigue of the reigning fatigue of generation of the be full of cracks that fatigure failure is caused is destructive to be reduced.Thereby the MV at rolling surface skin section observed center of gravity diameter through said 500 times SEM that will carry out the core aluminium alloy plate of the laminated wood after the heating suitable with soldering is that the average number density of the dispersed particle more than the 1 μ m is limited in 6000/mm ²Below.The average number density of this dispersed particle preferably is made as 4000/mm ²Below, more preferably be made as 2000/mm ²Below.

On the other hand; For the number density of the above-mentioned dispersed particle of the core aluminium alloy plate that suppresses to have carried out the laminated wood after the heating suitable with soldering, the average number density of the above-mentioned dispersed particle of the core aluminium alloy plate in the layer of feed stock material plywood stage before the heat-processed when standing soldering is stipulated.

That is, if the average number density of the above-mentioned dispersed particle of the core aluminium alloy plate in layer of feed stock material plywood stage is not set at 7000/mm ²Below, even for example the heat-processed of the number density of dispersed particle when standing soldering reduces (minimizing), can not guarantee that (guaranteeing) carried out the average number density of above-mentioned dispersed particle of the core aluminium alloy plate of the laminated wood after the heating suitable with soldering.Thereby, be that the average number density of the dispersed particle more than the 1 μ m is defined as 7000/mm with the MV at the center of gravity diameter observed of the core aluminium alloy plate in layer of feed stock material plywood stage through 500 times SEM ²Below.The preferred 5000/mm of the average number density of this dispersed particle ²Below, more preferably 3000/mm ²Below.

Intermetallic compound between the element that these dispersed particles contain for alloying element such as Si, Cu, Mn, Ti or quilt such as Fe, Mg as stated, reach the intermetallic compound of these elements and Al.The size of dispersed particle and number density and forming element (composition) are irrelevant, and the antifatigue destructiveness of the reigning fatigue of crevasse crack propagation (speed) is had considerable influence, therefore, among the present invention, as stated, its size and number density are stipulated.

The size of these dispersed particles and the mensuration of average number density are to observe through with the SEM (scanning electron microscope) of 500 times of multiplying powers the tissue of the rolling surface skin section of above-mentioned core aluminium alloy plate being carried out 10 visuals field, and it are carried out image analysis implement.Thus, the MV that can measure each center of gravity diameter is that the average number density of the above dispersed particle of 1 μ m is (individual/mm ²).

(the number density control of the dispersed particle of the application's first invention and the 3rd invention)

The control of average number density that these have made the dispersed particle of regulation is through in equal thermal treatment (thermal treatment homogenizes), the number density of the dispersed particle of separating out in the heat-processed of equal thermal treatment is exceedingly increased and carries out.For the number density with the precipitate of these sizes was made as in the stage as raw-material core aluminium alloy plate (ingot bar), can not make being increased to of average number density of above-mentioned dispersed particle surpass 7000/mm ², when after arriving soaking temperature, beginning hot rolling behind the maintenance certain hour, finishing the back from equal thermal treatment is below 30 minutes to beginning hot rolled time set.To reach soaking temperature be more than 450 ℃ and do not produce the such higher temperature of ratio of burning (burning).When this soaking temperature is lower than 450 ℃, the effect of just do not homogenize (soaking).But; Because the equal thermal treatment to this core aluminium alloy plate (ingot bar) is under than higher temperature, to carry out; So; Different because of the fusing point of sacrificing impregnating material (plate) and solder (plate), sacrifice at these that have under range upon range of state of impregnating material (plate) and solder (plate) can not be to the situation of the capable equal thermal treatment of core.In this case, preferably only core duraluminum ingot bar is carried out the equal thermal treatment of above-mentioned relatively pyritous, thereafter, the laminated wood of range upon range of state compared cryogenic equal thermal treatment and be used for the hot rolled reheat handle.

(the core aluminium alloy plate tissue of the application's second invention and the 4th invention)

Then, the core aluminium alloy plate in the laminated wood of the application's second invention and the 4th invention is described.

At this, laminated wood or carried out the heating suitable (thermal process) with soldering after laminated wood in the core aluminium alloy plate, same with the application first invention and the 3rd invention, form by 3000 line aluminium alloys and to constitute.

In the application's second invention and the 4th invention; For the antifatigue of the reigning fatigue of crevasse crack propagation (speed) that fatigure failure is caused that improves this core aluminium alloy plate destructive, to the MV at the center of gravity diameter observed of the rolling surface thickness of slab central part of the average crystal grain diameter of the rolling direction in the longitudinal section of rolling direction of this core aluminium alloy plate (only regulation has been carried out the laminated wood after the heating suitable with soldering) and this core aluminium alloy plate through 50000 times TEM be the scope precipitate of 0.1～0.5 μ m average number density (laminated wood and carried out the heating suitable with soldering after laminated wood) stipulate.

(crystal grain of the application's second invention and the 4th invention)

As stated; Under the situation as above-mentioned thickization of average crystal grain diameter of the core aluminium alloy plate that has carried out the preceding layer of feed stock material plywood of laminated wood or assembling (thermal process) after the heating suitable with soldering, the destructive reduction of antifatigue of the reigning fatigue of generation of the be full of cracks that fatigure failure is caused.Thereby, make below average crystal grain diameter miniaturization to the 200 μ m of the rolling direction in the longitudinal section of rolling direction of the core aluminium alloy plate in the laminated wood that has carried out after the heating suitable, below the preferred 150 μ m with soldering.Also have, in order to make the core aluminium alloy plate miniaturization like this in the laminated wood that has carried out after the heating suitable, need be made as the average crystal grain diameter of the core aluminium alloy plate of layer of feed stock material plywood below the 200 μ m in advance certainly, below the preferred 150 μ m with soldering.But; Even stipulated the above-mentioned average crystal grain diameter of the core aluminium alloy plate of layer of feed stock material plywood, different change (thickization) of heating condition of soldering processing the when average crystal grain diameter that has carried out the laminated wood after the heating suitable with soldering also can be made because of heat exchanger etc.Therefore, different even stipulated the above-mentioned average crystal grain diameter of core aluminium alloy plate because of above-mentioned heating condition in the stage of layer of feed stock material plywood, also have and depart from afore mentioned rules and the possibility of thickization needn't specially be stipulated in the layer of feed stock material plywood stage.

Also have, said here crystal grain diameter is the crystal grain of the rolling direction in the longitudinal section (section of the plate after cutting off along rolling direction) in rolling direction.This crystal grain diameter is the longitudinal section in the rolling direction of the core aluminium alloy plate (extraction test portion) to the layer of feed stock material plywood and in the laminated wood after having carried out the heating suitable with soldering; Carry out observing with 50 times opticmicroscope after the pre-treatment through mechanical mill, electrolytically etching.At this moment, draw straight line, be used as each crystal grain diameter and the process of chopping (line intercept method) measured is measured the slice length that is positioned at each crystal grain on this straight line to above-mentioned rolling direction.Carry out said determination at 10 positions arbitrarily, calculate average crystal grain diameter.At this moment, measure line length for 1 and be made as more than the 0.5mm, the mensuration line in per 1 visual field is made as 3, per 1 location is carried out 5 visuals field observe.Then, according to per 1 visual field (measure line 3), per 5 visual field/1 location, per 10 location, to per 1 average crystal grain diameter of measuring the line sequentially determining averaging successively, as said average crystal grain diameter among the present invention.

(precipitate of the application's second invention and the 4th invention)

Carried out laminated wood after the heating suitable when (packing into) no matter the core aluminium alloy plate is a brazing sheet or be assembled into, all must be heated near the temperature 600 ℃ when carrying out soldering with soldering.Even stand such heat-processed, the above-mentioned chemical ingredients composition of stipulating among the present invention etc. can not change yet.But; The average number density of the precipitate of the scope of 0.1～0.5 above-mentioned μ m that stipulates among the present invention is because solid solution and thickization etc., can be towards changing than above-mentioned layer of feed stock material plywood direction still less in above-mentioned laminated wood after having carried out the heating suitable with soldering.

In the application's second invention and the 4th invention; For the antifatigue that improves in the reigning fatigue of crevasse crack propagation (speed) that fatigure failure causes destructive, to above-mentioned layer of feed stock material plywood and the average number density of the above-mentioned precipitate of the core aluminium alloy plate in the laminated wood after having carried out the heating suitable with soldering stipulate.In other words, the average number density of the above-mentioned precipitate of the heat exchanger component of the heat-processed under near the temperature above-mentioned 600 ℃ when having stood soldering is stipulated.

The average number density of above-mentioned precipitate of having carried out the core aluminium alloy plate of the laminated wood after the heating suitable with soldering surpasses 80/μ m ³Situation under, reduce to the antifatigue of the reigning fatigue of crevasse crack propagation (speed) is destructive.Thereby the MV that passes through the observed center of gravity diameter of above-mentioned 50000 times TEM at rolling surface thickness of slab central part that will carry out the core aluminium alloy plate of the laminated wood after the heating suitable with soldering is that the average number density of precipitate of the scope of 0.1～0.5 μ m is set at 80/μ m ³Below.In addition, be that the average number density of above-mentioned precipitate of the size of 0.2～0.5 mu m range is set at 70/μ m preferably with the MV of center of gravity diameter ³Below.

On the other hand; For the number density of the above-mentioned dispersed particle of the core aluminium alloy plate that suppresses to have carried out the laminated wood after the heating suitable with soldering, the average number density of the above-mentioned precipitate of the core aluminium alloy plate in the layer of feed stock material plywood stage before the heat-processed when standing soldering is stipulated.

That is, if the average number density of the above-mentioned precipitate of the core aluminium alloy plate in layer of feed stock material plywood stage is not set at 150/μ m ³Below, even for example the heat-processed of the number density of precipitate when standing soldering reduces (minimizing), can not guarantee the average number density of the above-mentioned precipitate of the core aluminium alloy plate in (guaranteeing) laminated wood after having carried out the heating suitable with soldering.Thereby; Among the present invention, is that the average number density of above-mentioned precipitate of the size of 0.1～0.5 mu m range is set at 150/μ m with the core aluminium alloy plate in layer of feed stock material plywood stage at the MV of rolling surface thickness of slab central part through the observed center of gravity diameter of 50000 times TEM ³Below.In addition, be that the average number density of above-mentioned precipitate of the size of 0.2～0.5 mu m range is set at 120/μ m preferably with the MV of center of gravity diameter ³Below.

These precipitates are intermetallic compound or the intermetallic compound of these elements and Al between the element that contains of alloying elements such as Si, Cu, Mn, Ti or quilts such as Fe, Mg as stated.And; Among the present invention; Stipulate with its size and average number density as stated, no matter be that its size and average number density all have considerable influence to the antifatigue destructiveness in the reigning fatigue of crevasse crack propagation (speed) because of any forming element of precipitate (composition).

The size of these precipitates and the mensuration of average number density through the tissue to the thick central part of the rolling panel, are carried out 10 visuals field with the TEM (transmission electron microscope) of 50000 times of multiplying powers and are observed, and observations is carried out image analysis and carried out.Thus, the MV that can measure each center of gravity diameter is that the average number density of the precipitate of 0.1～0.5 mu m range is (individual/μ m ³).

(the number density control of the precipitate of the application's second invention and the 4th invention)

The control of the average number density of the precipitate of these regulations is to carry out through the number density that in equal thermal treatment (thermal treatment homogenizes), reduces the precipitate that crystallization goes out in the castingprocesses.In order the number density of the precipitate of these sizes to be reduced to 50/μ m in stage of core aluminium alloy plate (ingot bar) ³Below, soaking temperature is controlled, soaking temperature is set at more than 500 ℃, and can produce the higher temperature of ratio of that kind overbumt.When this soaking temperature is lower than 500 ℃, can not reduce the number density of the precipitate that crystallization goes out in the castingprocesses.But; Because the equal thermal treatment to this core aluminium alloy plate (ingot bar) is under than higher temperature, to carry out; So; Different because of the fusing point of sacrificing impregnating material (plate) and solder (plate) sometimes, can not have under these states of sacrificing impregnating material (plate) and solder (plate) range upon range of, core is carried out equal thermal treatment.In this case, preferably only core duraluminum ingot bar is carried out the above-mentioned relatively equal thermal treatment of pyritous, thereafter, the laminated wood of range upon range of state is implemented more cryogenic equal thermal treatment or is used for the processing of hot rolled reheat.

(al alloy component of the application's invention)

Below, explain that the duraluminum of each member of the laminated wood that constitutes the application's first invention～the four invention (following, be generically and collectively referred to as the application's invention) is formed.Core aluminium alloy plate 2 is made up of 3000 line aluminium alloys as stated.Core aluminium alloy plate 2 is used member as heat exchangers such as tubing and collector materials, not only requires to have the tissue of regulation in the application's invention, in addition, also requires all characteristics such as plasticity, solderability or weldableness, intensity, corrosion stability.

Therefore; The core aluminium alloy plate of the application's invention is that following duraluminum is formed: contain Si:0.2～1.5 quality %, Cu:0.2～1.2 quality %, Mn:0.2～1.4 quality %, Ti:0.03～0.3 quality % respectively; And contain below the Fe:1.0 quality %, surplus is made up of Al and unavoidable impurities.

At this, preferred above-mentioned aluminium alloy plate also contains one or more among Cr:0.03～0.3 quality %, Zn:0.2～1.0%, the Zr:0.03～0.3 quality %.In addition, preferably contain the following Mg of 0.5 quality %.

Element beyond above-mentioned Fe, Mg and the above-mentioned record element is essentially impurity.But; Consider from the viewpoint of the recycle of aluminium alloy plate; As molten material; Not only use raffinal base material (Japanese: ア Le ミニウ system ground gold), and use 6000 to be alloy or other aluminium alloy scrap, low-purity aluminium base (Japanese: ア Le ミニウ system ground is golden) etc. during, also can sneak into these elements as melt raw material.And, these elements being reduced to for example detect below the boundary, self cost will improve, and therefore need allow to contain to a certain extent.Thereby, allow to contain in the scope that does not hinder the object of the invention and effect.For example, as long as above-mentioned element in addition such as B contains respectively below 0.05%.

Si:0.2～1.5 quality %

Si and Fe form intermetallic compound, to improve the intensity of core aluminium alloy plate.In order to ensure the layer of feed stock material plywood and the necessary strength of the laminated wood after having carried out the heating suitable with soldering, Si content need be for more than the 0.2 quality %.On the other hand, when Si content is too much, form thick compound in the core, the layer of feed stock material plywood and carried out the heating suitable with soldering after the corrosion stability of laminated wood reduce, therefore, Si content is set at below the 1.5 quality %.Thereby the content range of Si is set at the scope of 0.2～1.5 quality %.

Cu:0.2～1.2 quality %

Cu is present in the aluminium alloy plate with solid solution condition, and the intensity of core aluminium alloy plate is improved.Therefore, in order to ensure the layer of feed stock material plywood and the necessary strength of the laminated wood after having carried out the heating suitable with soldering, Cu content need be for more than the 0.2 quality %.On the other hand, when Cu content is too much, the layer of feed stock material plywood and carried out the heating suitable with soldering after the corrosion stability of laminated wood reduce, therefore, Cu content is set at below the 1.2 quality %.Thereby the content range of Cu is set at the scope of 0.2～1.2 quality %.

Mn:0.2～1.4 quality %

Mn is distributed in the aluminium alloy plate intermetallic compound of the dispersed particle of defined etc., can not reduce the corrosion stability of core aluminium alloy plate, is to be used to element that intensity is improved.In addition, Mn also has the crystal grain diameter of making miniaturization, improves the anti-fatigue characteristic of shaking, reaches the destructive effect of the pairing antifatigue of the reigning fatigue of generation that improves the be full of cracks that causes because of fatigure failure.Therefore, in order to ensure above-mentioned laminated wood and the necessary strength of the laminated wood after having carried out the heating suitable with soldering, it is destructive to improve antifatigue, makes it to contain more than below being limited to 0.2 quality %.

On the other hand, when Mn content was too much, the number density of dispersed particle was compared with regulation and is become too much, made the anti-fatigue characteristic of shaking, and destructive reduction of the pairing antifatigue of the reigning fatigue of generation of the be full of cracks that causes of fatigure failure on the contrary.In addition, the plasticity of aluminum alloy laminate reduces, and is adding man-hour to the shaping of part shape etc., and aluminum alloy laminate might crack.Therefore, Mn content is set at below the 1.4 quality %.Thereby the content range of Mn is set at the scope of 0.2～1.4 quality %.In addition, preferably the content range with Mn be set at more than the 0.2 quality %, below the 1.0 quality %, more preferably 0.2 quality % above, below the 0.6 quality %.

Ti:0.03～0.3 quality %

Ti forms fine intermetallic compound in aluminium alloy plate, have the effect of the corrosion stability that improves the core aluminium alloy plate.Therefore, in order to ensure above-mentioned laminated wood and the corrosion stability of necessity of the laminated wood after having carried out the heating suitable with soldering, Ti content need be for more than 0.03%.And Ti content is when too much, and the plasticity of aluminum alloy laminate reduces, and to the man-hour that adds of the shaping of part shape etc., aluminum alloy laminate might crack.Therefore, Ti content is set at below 0.3%.Thereby the content range of Ti is set at the scope of 0.03～0.3 quality %.

Below the Fe:1.0 quality %

Fe just must contain in the core aluminium alloy plate as long as use waste material as the aluminum alloy melting raw material.As stated, Fe and Si form intermetallic compound and improve the intensity of core aluminium alloy plate, and make the crystal grain diameter miniaturization, also have the effect of the solderability that improves core.But when the content of Fe was too much, the corrosion stability of core aluminium alloy plate significantly reduced.Therefore, Fe content is limited in below the 1.0 quality %.

Below the Mg:0.5 quality %

Mg can improve the intensity of core aluminium alloy plate.But the content of Mg is fluoridized in aluminum brazing flux (Nocolok) braze welding etc. of system soldering flux in use for a long time, and solderability reduces.Therefore, when the heat exchanger towards can cause the such soldering condition of solderability reduction because of Mg under, Mg content is preferably limited to below 0.5%.

Among Cr:0.03～0.3 quality %, Zn:0.2～1.0 quality %, the Zr:0.03～0.3 quality % one or more

Cr, Zn, Zr have the anti-fatigue characteristic of shaking that improve the core aluminium alloy plate, and the effect of the reigning fatigue characteristic of generation of the be full of cracks that causes of fatigure failure.When bringing into play this effect, the scope at Cr:0.03～0.3 quality %, Zn:0.2～1.0 quality %, Zr:0.03～0.3 quality % contains one or more.

(solder alloy of the application's invention)

Be coated on the solder alloy 4 on the core aluminium alloy plate 2, just can use at present the Al-Si that is at widely used JIS4043,4045,4047 etc. 4000 is known solder duraluminums such as solder alloy.Solder alloy is sacrificed impregnating material (plate) 3 and has been coated the brazing sheet of aluminium alloy brazing material (plate) 4 and constitute at another side as coated aluminium alloy plate in one side.

(the sacrifice impregnating material of the application's invention)

Be coated on that sacrifice impregnating material alloy 3 on the core aluminium alloy plate 2 just can use at present at 7000 line aluminium alloys such as JIS7072 of widely used Al-1 quality %Zn composition etc., to contain Zn be known sacrifice impregnating material duraluminum.It is necessary in heat exchanger that this sacrifice impregnating material is present in the automobile of managing inner face side at water coolant.That is, in order to ensure corrosive anticorrosion, the corrosion stability of the pipe inner face side that exists to water coolant, sacrificing impregnating material becomes necessary material.

Embodiment

< first experimental example (the application's first invention and the 3rd inventive embodiment) >

Below, enumerate embodiment the application's first invention and the 3rd invention are more specifically described.

Process the laminated wood (brazing sheet) 1 of duraluminum core 2, the tissue of core 2 is investigated with the A shown in the table 1～R composition.Again for the 1 simulation soldering of this laminated wood, implement to be equivalent to 600 ℃ temperature carry out soldering in 3 minutes heating, keep after, cool off for 100 ℃/minute with average cooling rate, investigation is equivalent to the tissue of the core part of the laminated wood after this soldering heating.These results are shown in table 2.In addition, the mechanical characteristics and the fatigue characteristic that are equivalent to the laminated wood after this soldering is heated are measured, estimated.These results are shown in table 3.

(manufacturing of laminated wood)

The manufacturing of laminated wood is following.3000 line aluminium alloy compositions of the composition of the A～R shown in the table 1 are carried out fusion, casting, make duraluminum core ingot bar.At the face of a side of this core ingot bar, coat by Al-1 quality %Zn and forms the JIS7072 aluminium alloy plate that constitutes as sacrificing impregnating material, form the JIS4045 aluminium alloy plate that constitutes as braze in the another side coating by Al-10 quality %Si.Then, as shown in table 2, in each example all to the soaking temperature of this cladding plate, finish the back from soaking and carry out various changes to the beginning hot rolled time, and control the number density of above-mentioned dispersed particle, on this basis, cladding plate is carried out hot rolling.Then, further implement suitable process annealing on one side and carry out cold rollingly, obtain the laminated wood (brazing sheet) that H14 modulates material.

Each example is general, and the thickness of slab of the core aluminium alloy plate of laminated wood is 0.18mm.Range upon range of respectively solder, the thickness of sacrificing impregnating material all are the scope of 20～30 μ m on each face of this core.

(tissue)

Use above-mentioned measuring method respectively; The tissue of the core part that to observe above-mentioned cold rolling cladding plate be laminated wood and the core part of each laminated wood after the above-mentioned heating, the MV that passes through the observed center of gravity diameter of 500 times SEM of measuring average crystal grain diameter (μ m), the rolling surface skin section of the rolling direction in the longitudinal section of rolling direction are that the average number density of the dispersed particle more than the 1 μ m is (individual/mm ²).These results are shown in table 2.At this; As the raw-material average crystal grain diameter that carries out the core aluminium alloy plate of the laminated wood before the heating suitable with soldering; Not expression in table 2; But pine for almost not changing because it adds in the above-mentioned soldering that is equivalent to the short period of time, therefore, the carrying out shown in itself and the table 2 average crystal grain diameter of the core aluminium alloy plate in the laminated wood after the heating suitable with soldering roughly the same.

(characteristic of machinery)

Carry out the tension test of each laminate after the above-mentioned heating, measure tensile strength (MPa), 0.2% yield strength (MPa), percentage elongation (%), the contraction percentage of area (Japanese: strand り) (%), the n value respectively.These results are shown in table 3.Test conditions is from No. 5 test films (25mm * 50mmGL * thickness of slab) of the JISZ2201 of the perpendicular direction of each laminated wood extraction and rolling direction, carries out tension test.Tension test is based on JISZ2241 (1980) (metal material stretching test method), under 20 ℃ of room temperatures, makes an experiment.In addition, pinblock speed is the 5mm/ branch, carries out rupturing up to test film with fixed speed always.The n value is endpoint calculation true stress and the true strain from yield extension, and being plotted in the transverse axis is strain, is on the logarithmic scale of stress with the longitudinal axis, the value of the collinear slope gained that the mensuration measuring point is represented.

(fatigue characteristic)

The evaluation of the fatigue characteristic of each laminated wood after the above-mentioned heating is to carry out at normal temperatures through known single vibration shape plain bending protracted test machine shown in Figure 3 of putting down in writing in the above-mentioned patent documentation 5.That is, on each laminated wood after the above-mentioned heating,, cut out the test film of 10mm * 60mm * thickness of slab, make test film with the mode parallel with rolling direction.Shown in the right side of Fig. 3, an end of this test film is installed in the fixation side of single vibration shape plain bending protracted test machine.And, shown in the left side of Fig. 3, with the other end of this test film of blade clamping of driving side.

Fatigue-bending test is through moving the position of this blade, thereby changes the test film cutting length on one side, Yi Bian make singly amplitude necessarily (above-below direction of Fig. 3 is 5mm) and the plain bending of the sheet that makes an experiment repeatedly.At this moment,, regulate the test film cutting length, add dependent variable that stress in bending reaches fracture portion than higher maximum about 0.005 so that pay for reigning fatigue takes place in the be full of cracks of reproducing as problem of the present invention.Under this condition, obtain the multiplicity that the plain bending of fracture takes place up to each test film.These results are shown in table 3.

Also have; About the dependent variable of fracture portion, owing to can not strain gauge directly be attached to fracture location, therefore; Strain gauge is attached to the position of the regulation at 2,3 places of leaving fracture location a little; Interrupt the dependent variable of splitting the position in the strain value of the strain gauge during according to each test film length, calculate the dependent variable of fracture location thus, regulating bearing strength test based on this is the test film cutting length.

(surface of fracture observation)

In addition, observe the rolling surface of the fatigure failure neighborhood of each laminated wood (being equivalent to above-mentioned soldering heating back) after the fatigue-bending test, according to the mechanism of the occurrence degree investigation fatigure failure of be full of cracks with 100 times SEM.Under the many situation of the occurrence degree of this be full of cracks, be that reigning fatigue takes place the be full of cracks as problem of the present invention, under the fewer situation of the occurrence degree of be full of cracks, be the reigning fatigue of crevasse crack propagation.Thereby; For congener aluminium alloy plate; (typically) made be full of cracks reigning fatigue of generation and the reigning fatigue of crevasse crack propagation consciously respectively, utilizes the test portion as benchmark, in advance the difference of its be full of cracks occurrence degree investigated.Then, compare, under the many situation of the occurrence degree of be full of cracks, be judged to be the reigning fatigue of crevasse crack propagation, under the fewer situation of the occurrence degree of be full of cracks, be judged to be the reigning fatigue of crevasse crack propagation with test portion as this benchmark.These results are shown in table 3.

[table 1]

* in the record of content ,-record be expressed as below the detectability.

[table 2]

[table 3]

As shown in table 2, in the invention example 1～13, the core aluminium alloy plate and is made at preferred soaking condition and range in composition compositing range of the present invention.Therefore, as shown in table 2, the core aluminium alloy plate of laminated wood (brazing sheet) has in its rolling surface skin section, the MV of observed center of gravity diameter is that the average number density of the dispersed particle more than the 1 μ m is at 7000/mm through 500 times SEM ²Following tissue.Thereby; Even as the laminated wood (brazing sheet) that has carried out after the heating suitable with soldering; Its core aluminium alloy plate also has like undertissue: the average crystal grain diameter of the rolling direction in the longitudinal section of rolling direction is also below 200 μ m; And the MV of its rolling surface skin section through the observed center of gravity diameter of 500 times SEM is that the average number density of the dispersed particle more than the 1 μ m is 6000/mm ²Below.

Consequently, as shown in table 3, invent example 1～13 except that intensity with regulation, excellents such as relative reduction in area, n value, the multiplicity of the fracture of the soldering respective material in fatigue-bending test is many, and fatigue lifetime is long.Thereby the such surface of fracture neighborhood surface observation results many from the occurrence degree of be full of cracks can know, invention example 1～13, and the application's first invention and the 3rd invention take place reigning tired excellent as the be full of cracks of problem.

In other words; With after in the comparison of each comparative example of stating, can find out, as invent example 1～13; If relative reduction in area is more than 85%, the n value is more than 0.32, the present invention's first invention and the 3rd invention take place reigning tired excellent as the be full of cracks of problem.

Relative therewith, though comparative example 14,15 core aluminium alloy plates (B) in the application invents the composition compositing range, the overlong time that comparative example 14 to hot rolling begins, comparative example 15 soaking temperatures are low excessively.Therefore, as shown in table 2, the average number density of the above-mentioned precipitate of the core aluminium alloy plate of laminated wood surpasses 7000/mm ²Thereby, though the above-mentioned average crystal grain diameter of core aluminium alloy plate below 150 μ m, the average number density of each its above-mentioned dispersed particle of laminated wood after the above-mentioned heating also surpasses 6000/mm ²

Consequently, as shown in table 3, though comparative example 14,15 has the intensity of regulation, relative reduction in area is lower than 85%, the n value is lower than 0.32, and these characteristics are poor.Therefore, the low repetition in the fatigue-bending test up to the fracture of soldering respective material, fatigue lifetime is short.Thereby, can know that according near many these observationss of occurrence degree of the be full of cracks of the rolled surface fracture portion in the comparative example 14,15, reigning tired variation takes place in be full of cracks.

In the comparative example 16～20, the core aluminium alloy plate has the one-tenth that departs from the scope of the invention and is grouped into N, O, P, Q, R (table 1).That is, the content of Si, Cu, Mn, Ti, Fe is too much, exceeds the upper limit separately respectively.Consequently, the low repetition of the fracture of the soldering respective material of each laminated wood after the above-mentioned heating in fatigue-bending test, fatigue lifetime is short.

Result according to above embodiment can prove, be used to make heat exchanger with laminated wood or the mechanical characteristics of the laminated wood after having carried out the heating suitable with soldering, and be full of cracks the important meaning or the effect of each important document of reigning tired excellent the application's first invention and the 3rd invention take place.

< the 2nd embodiment (the application's second invention and the 4th inventive embodiment) >

Below, enumerate embodiment the application's second invention and the 4th invention are more specifically described.

Making has the laminated wood (brazing sheet) 1 of the duraluminum core 2 of a shown in the table 4～r composition, the tissue of investigation core 2 parts.In addition, this laminated wood 1 is simulated soldering, be equivalent to 600 ℃ temperature implement soldering in 3 minutes heating, keep after, cool off for 100 ℃/minute with average cooling rate, investigation is equivalent to the tissue of the core part of the laminated wood after this soldering heating.These results are shown in table 5.In addition, the mechanical characteristics and the fatigue characteristic that are equivalent to the laminated wood after this soldering is heated are measured, estimated.These results are shown in table 6.

(manufacturing of laminated wood)

The manufacturing of laminated wood is carried out as follows.The 3000 line aluminium alloy compositions that a shown in the table 4～r is formed melt, cast and make duraluminum core ingot bar.Only this core ingot bar soaking temperature that makes as shown in table 5 is carried out various variations, the number density of control precipitate (represented soaking temperature is the equal thermal treatment temp that only is directed against the core ingot bar in the table 5).Afterwards, coat the JIS7072 aluminium alloy plate that constitutes by Al-1 quality %Zn composition in the one side of core ingot bar as sacrificing impregnating material, coat the JIS4045 aluminium alloy plate that constitutes by Al-10 quality %Si composition as braze at another side.Then, the scope of this cladding plate reheat to 500～530 ℃ is carried out hot rolling.At this moment, finishing the back from reheat was fixed as 30 minutes to beginning the hot rolled time.Then, carry out cold rollingly, be made for the laminated wood (brazing sheet) of H14 modulation material while implement suitable process annealing again.

Each example is general, and the thickness of slab of the core aluminium alloy plate of laminated wood is 0.18mm.Thickness at the range upon range of respectively solder of each face of this core, sacrifice impregnating material is the scope of 20～30 μ m.

(tissue)

Adopt above-mentioned measuring method respectively; The tissue of the core part that to observe above-mentioned cold rolling cladding plate be laminated wood and the core part of each laminated wood after the above-mentioned heating, the average crystal grain diameter (μ m), rolling surface thickness of slab central part of measuring the rolling direction in the longitudinal section of the rolling direction MV through the observed center of gravity diameter of 50000 times TEM is that the average number density of precipitate of scope of 0.1～0.5 μ m is (individual/μ m ³).These results are shown in table 2.Also have,, utilize equal thick interference fringe to obtain the test portion thickness of look-out station, the number of the precipitate of the per unit volume of mensuration test portion about the average number density of precipitate.At this; Do not represent the average crystal grain diameter that carries out the core aluminium alloy plate of the laminated wood before the heating suitable as raw-material in the table 5 with soldering; But, it pines for almost not changing because adding in the soldering that is equivalent to the above-mentioned short period of time; Therefore, with the carrying out shown in the table 5 average crystal grain diameter of the core aluminium alloy plate in the laminated wood after the heating suitable with soldering roughly the same.

(mechanical characteristics)

Carry out each the laminated wood tension test after the above-mentioned heating, measure tensile strength (MPa), 0.2% ys (MPa), unit elongation (%), relative reduction in area (%), n value respectively.These results are shown in table 6.Test conditions carries out tension test for No. 5 test films (25mm * 50mmGL * thickness of slab) that extract from each laminated wood with the JISZ2201 of the perpendicular direction of rolling direction.Tension test is based on JISZ2241 (1980) (metal material stretching test method), under 20 ℃ of room temperatures, makes an experiment.In addition, pinblock speed is 5mm/ minute, up to test film fracture takes place and carries out with fixed speed always.The n value is endpoint calculation true stress and the true strain from yield extension, and being plotted in the transverse axis is strain, is on the logarithmic scale of stress with the longitudinal axis, measures the value of the straight slope gained that measuring point representes in 0.05～0.10 the scope of really being deformed into.

(fatigue characteristic)

The evaluation of the fatigue characteristic of each laminated wood after the above-mentioned heating is to carry out at normal temperatures with known single vibration shape plain bending protracted test machine shown in Figure 3 of being put down in writing in the above-mentioned patent documentation 5.That is the test film that, cuts out 10mm * 60mm * thickness of slab with the mode that parallels with rolling direction on each laminated wood after the above-mentioned heating is made test film.Shown in the right side of Fig. 3, an end of this test film is installed on the fixation side of single vibration shape plain bending protracted test machine.And, shown in the left side of Fig. 3, with the other end of this test film of blade clamping of driving side.

Fatigue-bending test is through moving the position of this blade, change the test film cutting length on one side, Yi Bian make singly amplitude necessarily (above-below direction of Fig. 3 is 5mm) and the plain bending of the sheet that makes an experiment repeatedly.At this moment,, regulate the test film cutting length, add the lower maximum about 0.008 of dependent variable that stress in bending is a fracture portion so that pay for reigning fatigue takes place in the be full of cracks of reproducing as problem of the present invention.Under this condition, obtain the multiplicity that the plain bending of fracture takes place up to each test film.These results are shown in table 6.

Also have; About the dependent variable of fracture portion, owing to can not strain gauge directly be attached to fracture location, therefore; Strain gauge is attached to the position of the regulation at 2,3 positions leaving fracture location a little; Interrupt the dependent variable of splitting the position in the strain value of the strain gauge during according to each test film length, calculate the dependent variable of fracture location thus, and to regulate bearing strength test as benchmark be the test film cutting length.

(surface of fracture observation)

In addition, observe the rolling surface of the fatigure failure neighborhood of each laminated wood (being equivalent to above-mentioned soldering heating back) after the fatigue-bending test, according to the mechanism of the occurrence degree investigation fatigure failure of be full of cracks with 100 times SEM.Being that reigning fatigue takes place for be full of cracks as problem of the present invention under the many situation of the occurrence degree of this be full of cracks, is the reigning fatigue of crevasse crack propagation under the fewer situation of the occurrence degree of be full of cracks.Thereby; For congener aluminium alloy plate; (typically) makes and tries to be divided into be full of cracks reigning fatigue of generation and the reigning fatigue of crevasse crack propagation consciously respectively, utilizes the test portion as benchmark, in advance the difference of its be full of cracks occurrence degree investigated.Then, compare, under the many situation of the occurrence degree of be full of cracks, be judged to be the reigning fatigue of crevasse crack propagation, under the fewer situation of the occurrence degree of be full of cracks, be judged to be the reigning fatigue of crevasse crack propagation with test portion as this benchmark.These results are shown in table 6.

[table 4]

* in the record of content ,-record be expressed as below the detectability.

[table 5]

[table 6]

As shown in table 5, in the invention example 21～33, the core aluminium alloy plate and is being made in preferred soaking condition and range in the application invents the composition compositing range.Therefore, as shown in table 5, in the core aluminium alloy plate of laminated wood (brazing sheet), size is that the average number density of precipitate of the scope of 0.1～0.5 μ m is 150/μ m ³Below.Therefore, as the laminated wood (brazing sheet) that has carried out after the heating suitable with soldering, the average number density of precipitate of scope that also has above-mentioned size and be 0.1～0.5 μ m is at 80/μ m ³Following tissue.

Its result is as shown in table 6, invention example 21～33 except that intensity with regulation, excellents such as relative reduction in area, n value, the multiplicity up to the fracture of soldering respective material in the fatigue-bending test is many, fatigue lifetime is long.Thereby, can know near surface observation result few this surface of fracture of occurrence degree of be full of cracks, in the invention example 21～33, reigning tired excellent as the crevasse crack propagation of the application's second invention and the 4th invention problem.

In other words; With after can find out in the comparison of each comparative example of stating; As invent example 21～33, if relative reduction in area is 84% or more, n value is more than 0.32, then the application second invents and is the 4th good as the reigning fatigue of the crevasse crack propagation of problem in inventing.

Relative therewith, in the comparative example 34,35, the core aluminium alloy plate is (B) in the application invents the composition compositing range, but soaking temperature is low excessively.Therefore, as shown in table 5, the core aluminium alloy plate of laminated wood, the average number density of its above-mentioned precipitate surpasses 50/μ m ³Thereby in each laminated wood after the above-mentioned heating, though the above-mentioned average crystal grain diameter of its core aluminium alloy plate is below the 200 μ m, the average number density of above-mentioned precipitate also surpasses 20/μ m ³

Its result is as shown in table 6, though comparative example 34,35 has the intensity of regulation, relative reduction in area is lower than 85%, the n value is lower than 0.32, and these characteristics are relatively poor.Therefore, less to the multiplicity of soldering respective material fracture in the fatigue-bending test, fatigue lifetime is short.Thereby, can know that from the few observations of degree that the be full of cracks of fracture portion neighborhood rolled surface takes place comparative example 34,35 is relatively poor in the reigning fatigue of crevasse crack propagation.

In the comparative example 36～40, the core aluminium alloy plate has the one-tenth that departs from the application's invention scope and is grouped into n, o, p, q, r (table 4).That is, the content of Si, Cu, Mn, Ti, Fe is too much, surpasses each upper limit.Consequently, the number of occurrence up to the fracture of soldering respective material of each laminated wood after the above-mentioned heating in fatigue-bending test is less, and fatigue lifetime is short.

Result according to above embodiment can prove, be used to make heat exchanger with laminated wood or the mechanical characteristics of the laminated wood after having carried out the heating suitable with soldering, and be full of cracks the important meaning or the effect of each important document of reigning tired excellent the application's second invention and the 4th invention take place.

Utilizability on the industry

According to the application invention, can provide aluminium alloy heat radiator pipe etc. carrying out the laminated wood after the heating suitable with soldering, and the laminated wood of aluminum alloy brazing sheet etc. can thin-walled property excellent in fatigue characteristics aluminum alloy laminate and carried out the heating suitable with soldering after laminated wood.Thereby the application invention is suitable for requiring the thin-walled property of radiator tube, and the aluminum alloy heat exchanger used etc. of the automobile of excellent in fatigue characteristics.

As stated, to the present invention at length, and be illustrated with reference to specific embodiment, self-evident but for the practitioner, do not break away from the spirit and scope of the present invention, can be in addition various changes of the present invention.The application is based on the invention of the Japanese patent application (Japan special hope 2008-299562) of the Japanese patent application (Japanese spy is willing to 2008-030679) of application on February 12nd, 2008, the Japanese patent application of application on February 12nd, 2008 (Japan spy hope 2008-030680) and application on November 25th, 2008, and its content is introduced into as reference at this.

Claims

1. aluminum alloy laminate, it is to comprise the core aluminium alloy plate at least and be coated on anticorrosion on the said core aluminium alloy plate and it is characterized in that with duraluminum expendable material, and aluminum alloy laminate through soldering formation heat exchanger,

Said core aluminium alloy plate is that following duraluminum is formed; Said duraluminum composition contains Si:0.2～1.5 quality %, Cu:0.05～1.2 quality %, Mn:0.3～1.8 quality %, Ti:0.03～0.3 quality % respectively; And contain below the Fe:1.0 quality %; And surplus is made up of Al and unavoidable impurities

Have following tissue: this core aluminium alloy plate be that the average number density of the precipitate of 0.1～0.5 mu m range is 150/μ m at the MV of rolling surface thickness of slab central part through the viewed center of gravity diameter of 50000 times TEM ³Below.

2. aluminum alloy laminate, it is to comprise the core aluminium alloy plate at least and be coated on the anticorrosion aluminum alloy laminate with the duraluminum expendable material on the said core aluminium alloy plate, it is characterized in that,

As the tissue after the suitable heating of soldering; Have following tissue: the average crystal grain diameter of the rolling direction in the longitudinal section of rolling direction of this core aluminium alloy plate is set at below the 200 μ m; And, this core aluminium alloy plate be that the average number density of the precipitate of 0.1～0.5 mu m range is 80/μ m at the MV of rolling surface thickness of slab central part through the observed center of gravity diameter of 50000 times TEM ³Below.

3. according to each described aluminum alloy laminate in the claim 1～2, wherein, said core aluminium alloy plate also contains one or more among Cr:0.03～0.3 quality %, Zn:0.2～1.0 quality %, the Zr:0.03～0.3 quality %.

4. according to each described aluminum alloy laminate in the claim 1～3, wherein, said core aluminium alloy plate also contains below the Mg:0.5 quality %.

5. according to each described aluminum alloy laminate in the claim 1～4, wherein, the thickness of slab of said core aluminium alloy plate is the thin-walled of not enough 0.25mm.

6. according to each described aluminum alloy laminate in the claim 1～5, wherein, the thickness of slab of said laminated wood is the thin-walled of not enough 0.3mm.